On New Year's Eve 1959, the team launching the new Sun City retirement community, the first such large-scale venture in America, sat around a table at Manuel's Place, a Mexican restaurant in Peoria, Ariz. The mood was anxious. For months the team had been running national advertising touting "An Active New Way of Life" for older people. The next morning was Sun City's grand opening. Would anyone show up?

The group had reason to be worried, according to materials from Sun City's Historical Society. Their boss, the formidable Del Webb, had already sunk $2 million into developing the community exclusively for the group he called "55 and better." The heart of the company's market research? A quick trip to the retirement haven of St. Petersburg, Fla., where one of Webb's lieutenants interviewed restless seniors perched on park benches. Every psychiatrist and gerontologist the Webb executives consulted had told them they were crazy; older people would never leave their friends and family to head off to the God-forsaken desert of 1960s Arizona.

And even if these retirees were willing to think about it, there were other hurdles. Breaking the uncomfortable silence around the table at Manuel's, Owen Childress, the manager responsible for sales at Sun City, voiced the question that had been plaguing him for months: "I'm worried. . . . How am I going to get a 30-year mortgage on a guy who is 65 years old?"

The next morning, however, the group found a scene they could never have imagined. Lined up for two miles were cars filled with older men and women, converging on Sun City from all over the country. Their destination: a converted cotton field where six model homes -- tiny Levittown-style dwellings christened the Nottingham, the Monticello, the Norfolk, the Sherwood, the Sierra and the Kentworth -- sat incongruously on the edge of a makeshift golf course.

By the end of the weekend, 100,000 people in all would turn up.

From those small blades of putting-green grass and that collection of modest homes, an entire industry would grow around the dream of retirement as leisure -- as the "golden years," a phrase coined by Webb and his company. Instead of being dreaded years of decline, retirement would become something people longed for. Through the magic of marketing, retirement no longer meant only the end of work. It was sold as the beginning of a new, even a better life.

This dream would not only transform what it meant to grow older in America, but would ultimately lay the seeds for today's alarm about the graying of the baby boom generation and the viability of Social Security and other pension programs. The unanswered question: How will we ever be able to afford a leisure class that makes up a quarter of the population?

The success of Sun City was fueled not only by the marketing genius of Webb and his company, but by the pent-up demand from people unhappy with their lot. A gradual marginalization of older people had taken place over the previous 25 years. While the goal of the Social Security Act in 1935 had been, as President Franklin D. Roosevelt said, to "give some measure of protection to the average citizen and to his family against the loss of a job and against poverty-ridden old age," a key side effect was to lure older workers out of the labor market to make room for the hordes of unemployed young people who were seen as a potential source of social unrest.

With the end of the Depression and World War II, growing numbers of Americans retired, but in doing so cut themselves off from work and thereby much of society. Rocking aimlessly on the porch, they assumed "roleless roles," in the words of a leading gerontologist of the time. As men and women began to live extended, healthier lives, and as the period between the end of work and the end of life grew steadily longer, the question of the purpose of this period in life grew more and more urgent and wrenching.

"Too old to work, too young to die," was how, in the late 1940s, labor leader Walter Reuther characterized the period of limbo waiting after the middle years. Even the language seemed to contribute to this conclusion; the word retirement comes from the old French retirer, meaning "to go off into seclusion."

Indeed, so many people so dreaded retirement during the early postwar years that it created economic as well as psychological issues. The financial services industry found it hard to sell pensions to Americans loath not only to plan for but even to think about the grim existence awaiting them at the end of their working days. Desperate, the pension purveyors realized that they needed to re-brand the entire concept of aging.

To make retirement more appetizing, pension and annuity marketers in the 1950s seized on the notion of aristocratic leisure, depicting retirement not as a fate for people too old to work yet too young to die, but as an age of liberation -- from responsibility, from work, from the constraints of midlife. It was the chance at a second childhood. Graying as playing. Addressing the National Industrial Conference Board in 1952, the vice president of the Mutual Life Insurance Co. urged America's major corporations to begin preparing employees for retirement at age 50. He called upon the assembled companies to do a better job promoting the idea "that old age can be beautiful, and that the best of life is yet to come."

It would take the better part of a decade, and Webb's entrepreneurial genius, for this new concept of the American dream to be fully realized. Once communities like Webb's Sun City and its chief rival, Leisure World, emerged as emblems of retirement, developers, the pension industry and a vast leisure sector followed. In a relatively brief period, they transformed the ideal of aging into one of an endless vacation.

And a remarkable transformation it was: In 1950, half the men over 65 remained in the workforce. By 2000 the number was less than 18 percent. At the same time, older adults emerged as the biggest consumers of leisure activities in America. Soon the goal of retirement was replaced by a new dream: early retirement.

A half-century later, America finds itself in the midst of a demographic revolution, propelled by the aging of 78 million baby boomers. By 2030 these individuals will make up between 20 percent and 25 percent of the overall population. A wave of "greedy geezers," some policy experts say, threatens to break upon us and wash away our fiscal health. While the full force of these demographics has yet to be felt, there is a degree of consensus in much of the current debate over Social Security and national savings: Graying means paying -- for those of us who are younger.

However, those who simply pair up the old lifestyle with demographic trends and declare that social insolvency lies ahead fail to understand that another transformation is unfolding in front of us. And it is as profound as the change that took place during the early days of Sun City.

The gift of longevity is behind the new shift in the way people think about retirement. In 1900 the average American lived to the not-so-ripe age of 47. Today that number is 77, and rising. And that's long enough for retirees to get bored. How much golf can you play?

As a result, now people seldom think of retirement as a final stage of life but rather as an interlude between stages. More and more individuals are "retiring" for a period to catch their breath before making the transition to a new chapter in life. Surveys show that the ideal of the golden years is going into eclipse.

But what's next for these individuals, many of whom face an identity crisis when they think about the future? Are they senior citizens? Elderly? They don't feel that way. Neither young nor old, they are finished with midlife, yet they can look forward to the likelihood of decades of vitality before becoming truly old. What might they rightly aspire to in the next phase? How will they define success?

While much about the evolution of goals and purpose of this period of life remains unclear, a central, defining feature is emerging. It is work. The vast majority of the boomers plan to continue working -- full-time, part-time, paid, unpaid -- in their so-called retirement years. According to a recent study by the AARP, nearly 80 percent of boomers are planning to continue in paid labor during their sixties and seventies. Already we've witnessed an uptick in the percentage of people over age 65 who choose to keep working.

This new generation of aging boomers seems poised to swap that old dream of the freedom from work for a new one built around the freedom to work -- in new ways, on new terms, to new ends. Indeed, inklings of such a vision are already appearing.

Consider a recent ad campaign from Home Depot and AARP announcing a new partnership to recruit older workers for the home renovation giant. Targeting men (and perhaps some women) who couldn't wait to get home from their midlife work to get to the toolshed, the campaign beckons them to trade in retirement for a new vision of what work can be. The slogan: "Passion Never Retires."

Fidelity Investments offers its own take. In a series of ads, the financial services company features an aging boomer in front of a classroom, graying temples, full of engagement. The message at the top: "What did you want to do before you started doing what you're doing?" (In AARP's recent research on the boomers and work, teaching was selected as the No. 1 preferred post-midlife occupation.) A few years ago, the Del Webb company even opened up a new Sun City outside not-particularly sunny Chicago, prompted in part by research showing that aging boomers want to remain near opportunities for continued work.

The trend is, of course, welcome news -- and not just for the public coffers. We now know that work is good for aging individuals themselves, for their health as well as their wallets. At the same time the nation faces the prospect of a labor shortage in many areas over the coming decades.

In the end, reinventing retirement will take more than marketing, more than coining today's equivalent of the golden years -- more even than retooling Social Security. It will require a new generation of policies, pathways and priorities.

A tall order, but the history of aging in America is one of innovation. Social Security and Medicare were invented out of whole cloth within the past 70 years. We didn't even have retirement communities or senior centers 50 years ago. In just half a century, we managed to redefine aging so thoroughly that the "golden" years image seemed as natural as the oxygen in the air.

Now, just 10 months before the first of tens of millions of baby boomers begin to turn 60, we need a transformation no less bold. We must create an aging America that swaps the old leisure ideal for one that balances the joys and responsibilities of engagement across the life span. And that could produce a society that works better for all generations.

Author's e-mail: mfreedman@civicventures.org

Marc Freedman is president of Civic Ventures, a San Francisco-based nonprofit organization that develops opportunities for older Americans to serve their communities. He is author of "Prime Time: How Baby Boomers Will Revolutionize Retirement and Transform America" (Public Affairs).

Buying into the retirement dream: On New Year's Day 1960, nearly 100,000 people flocked to see six model homes for Sun City, Ariz., which helped redefine retirement. Built on former cotton fields near Phoenix, it featured a golf course, recreation center and shopping center. By 2000, it had 38,309 residents, whose median age was 75.